题目

As time goes on, I am no longer young, I have friends whose mothers have passed away.  I have heard these sons and daughters say they never fully appreciated their mothers   1   it was too late to tell them. I am blessed with the dear mother who is still alive. I   2   her more each day. My mother does not change, but I   3  . As I grow older and wiser, I realize   4   an extraordinary' person she is. How   5   that I am unable to speak these words in her   6  , but they flow easily from my pen.     As a daughter, how to thank her mother for life itself?? For the lov将一定量的Na、Na2O、Na2O2的混合物与足量的水反应，在标准状况下得到a L混合气体。将该混合气体通过电火花引燃，恰好完全反应，则原混合物中Na、Na2O、Na2O2的物质的量之比可能为（ ）A．2：1：2 B．1：1：2 C．2：2：1 D．1：1：1